Guiding principles for rewilding

Economics of rewilding

Rewilding, a concept often defined as an open-ended approach to ecological restoration that aims to establish self-sustaining ecosystems, has gained much interest in recent conservation science and practice. The economic dimensions of rewilding remain understudied, despite repeated calls for research, and we find that synthetic or programmatic contributions to the scientific literature are still missing. Here, we mined Scopus and Web of Science databases through a systematic review, looking for "rewilding" with various economic terms in the peer-reviewed literature, in the English language. We then screened out a 257 references-rich corpus with 14 variables, including the position of rewilding regarding positive and negative economic effects in specific sectors, and geographical or ecological foci. Our corpus amounts to ca. 40% of recent rewilding literature, with a clear emphasis on European study sites and the economic consequences of rewilding initiatives. Rewilding studies often refer to positive economic impacts on tourism and hunting, e.g., through higher income and employment rates, although very few studies properly quantify these. Conversely, most authors find rewilding harms farming, which is threatened by abandonment and damages by wildlife, raising interest in potential EU subsidy regimes. We highlight the surprising paucity of rewilding literature truly focusing on economics and/or providing detailed quantification-with remarkable exceptions. While rewilding's ecological relevance is no longer in question, demonstrating its economic benefits and sustainability will undoubtedly help scaling up. Thus, we advise rewilders to systematically measure and report investments and outcomes of rewilding initiatives, and to adopt common standards for cost and benefit assessments.

An assessment of future rewilding potential in the United Kingdom

Restoring ecosystems is an imperative for addressing biodiversity loss and climate change, and achieving the targets of the Kunming-Montreal Global Biodiversity Framework. One form of restoration, rewilding, may have particular promise but may also be precluded by requirements for other forms of land use now or in the future. This opportunity space is critical but challenging to assess. We explored the potential area available for rewilding in Great Britain until the year 2080 with a multisectoral land-use model with several distinct climatic and socioeconomic scenarios. By 2080, areas from 5000 to 7000 km2 were either unmanaged or managed in ways that could be consistent with rewilding across scenarios without conflicting with the provision of ecosystem services. Beyond these areas, another 24,000-42,000 km2 of extensive upland management could provide additional areas for rewilding if current patterns of implementation hold in the future. None of these areas, however, coincided reliably with ecosystems of priority for conservation: peatlands, ancient woodlands, or wetlands. Repeatedly, these ecosystems were found to be vulnerable to conversion. Our results are not based on an assumption of support for or benefits from rewilding and do not account for disadvantages, such as potential losses of cultural landscapes or traditional forms of management, that were beyond the modeled ecosystem services. Nevertheless, potential areas for rewilding emerge in a variety of ways, from intensification elsewhere having a substantial but inadvertent land-sparing effect, popular demand for environmental restoration, or a desire for exclusive recreation among the wealthy elite. Our findings therefore imply substantial opportunities for rewilding in the United Kingdom but also a need for interventions to shape the nature and extent of that rewilding to maintain priority conservation areas and societal objectives.

Wilding cities for biodiversity and people: a transdisciplinary framework

Accelerating urbanisation and associated lifestyle changes result in loss of biodiversity and diminished wellbeing of people through fewer direct interactions and experiences with nature. In this review, we propose the notion of urban wilding (the promotion of autonomous ecological processes that are independent of historical land-use conditions, with minimal direct human maintenance and planting interventions) and investigate its propensity to improve biodiversity and people-nature connections in cities. Through a large interdisciplinary synthesis, we explore the ecological mechanisms through which urban wilding can promote biodiversity in cities, investigate the attitudes and relations of city dwellers towards urban wild spaces, and discuss the integration of urban wilding into the fabric of cities and its governance. We show that favouring assembly spontaneity by reducing planting interventions, and functional spontaneity by limiting maintenance practices, can promote plant diversity and provide ecological resources for numerous organisms at habitat and city scales. These processes could reverse biotic homogenisation, but further studies are needed to understand the effects of wilding on invasive species and their consequences. From a socio-ecological perspective, the attitudes of city dwellers towards spontaneous vegetation are modulated by successional stages, with grassland and woodland stages preferred, but dense shrubby vegetation stages disliked. Wild spaces can diversify physical interactions with nature, and enrich multi-sensory, affective and cognitive experiences of nature in cities. However, some aspects of wild spaces can cause anxiety, feeling unsafe, and the perception of abandonment. These negative attitudes could be mitigated by subtle design and maintenance interventions. While nature has long been thought of as ornamental and instrumental in cities, urban wilding could help to develop relational and intrinsic values of nature in the fabric of cities. Wildness and its singular aesthetics should be combined with cultural norms, resident uses and urban functions to plan and design urban spatial configurations promoting human-non-human cohabitation. For urban wilding to be socially just and adapted to the needs of residents, its implementation should be backed by inclusive governance opening up discussion forums to residents and urban workers. Scientists can support these changes by collaborating with urban actors to design and experiment with new wild spaces promoting biodiversity and wellbeing of people in cities.

Spatial Distribution and Hierarchical Behaviour of Cattle Using a Virtual Fence System

Interest in virtual fencing has increased due to its flexibility for agriculture and rewilding. However, systems like Nofence© require large financial investments, and the need for individual collars complicates large-scale use. If cattle herds maintain cohesive groups around leading individuals, fewer collars could be used, thereby enhancing cost efficiency. This study investigates the pattern in spatial distribution in a herd of 17 Angus cows on Fanø in Denmark with GPS locations, using a Nofence© system. The aim of this paper is to determine how individuals position themselves in a herd, spatially, and identify a pattern in ranks. The method used in this study examines the distances between an individual to the rest of the herdmates using nearest neighbour and descriptive statistics. Contrary to expectations, this study did not reveal a distinct pattern in herd distribution. While some tendencies in spatial distribution patterns were observed, only a low concordance could be found (W=0.15,p<0.001), indicating great variability in the cattle's ranks. A cumulative curve of the ranks estimated over the entire periods, however, allowed a rough estimation of the hierarchy and allowed identification of the highest-ranked cows, making the use of a cumulative curve a possible solution to finding the high-ranked cows. This research underscores the complexity of cattle social structures and highlights the need for extended observation periods and alternative methodologies to enhance the cost-effectiveness and scalability of virtual fencing in agricultural and rewilding contexts.

The place for people in rewilding

Rewilding, although controversial, is increasingly presented as humanity's best hope of addressing the global biodiversity crisis, but it remains unclear how restoring nonhuman autonomy affects people's relationships with nature. We conceptualized 3 human-nature relationships (HNRs) that could occur when restoring nonhuman autonomy: human-nature dichotomy, human-nature compromise, and human-nature mutualism. Through 51 interviews, we then empirically tested the occurrence of these HNRs across diverse actors living and working in 2 longstanding British rewilding initiatives to better understand the place for people in rewilding. Actors' HNRs aligned with the 3 conceptual framings, but these relationships were complex. Individuals often demonstrated multiple perspectives that transcended conventional actor categorization. The tripartite framing also revealed conflicting values across and within individuals, resulting in pluralistic HNRs. Our work adds to the theory and practice surrounding the place for people in rewilding by cautioning against a single preferred HNR when restoring nonhuman autonomy and advocating that a diversity of human interactions with nature should be integrated into the global rewilding movement.

Sustaining altitude pastures in mountain landscapes-a fuzzy cognitive model approach

Similarly to other European mountain areas, in Serra da Estrela the grazing pressure has been reducing due to social and economic drivers that have pushed shepherds and sheep to the foothill, or plainly out of the sector. Shrub encroachment on commons and other previously grazed land is one of the most tangible effects of pastoral abandonment in Serra de Estrela. The impacts of the resulting increase in landscape continuity and biomass availability were made clear in the severe fires of 2017 and 2022. As fire risk is likely to increase with climate change, it becomes urgent to understand what strategies can be deployed to keep fragmentation in these landscapes. Key actors such as shepherds should be involved in this discussion to understand their perceptions, points of view and reasons for abandoning upland pastures. In this study, we use fuzzy cognitive mapping to identify the key variables and mechanisms affecting the pastoral system according to local shepherds. In our study, we developed with local stakeholders a framework outlining the local pastoral system. Based on that, we carried out the fuzzy cognitive mapping collecting 14 questionnaires. We found that shepherds' income is a central issue, but that it is highly dependent on many factors. Increasing the Common Agricultural Policy payments alone is not enough to incentivise the use of upland pastures. More targeted strategies, such as more support for shrub clearing, and direct payments conditional to transhumance are more impactful. Despite a contentious discourse between conservation and shepherding values in Serra da Estrela, we find that shepherd's values are aligned with biodiversity conservation and a potential nature-based solution for minimizing fire risk through woody fuel management. This opens up possibilities for new governance strategies, that put Serra da Estrela's social, environmental and cultural values at its core.

Wetland butterfly thriving in abandoned jungle: Neptis rivularis in the Czech Republic

With ongoing insect declines, species expanding in distribution and abundance deserve attention, as understanding their success may help design conservation strategies for less successful species. Common causes of these successes include warmer climates, novel resources, and exploiting land use change, including land abandonment. These factors affect the nymphalid butterfly Neptis rivularis, developing on Spiraea spp. shrubs and reaching the north-western limits of its trans-Palearctic distribution in Central Europe. We combined mark-recapture, behaviour analysis, and distribution modelling to study N. rivularis in wetlands of the Třeboňsko Protected Landscape (IUCN category V). The long-living adults (up to 4 weeks) spent a considerable amount of time searching for partners, ovipositing and nectaring at Spiraea shrubs, alternating this with stays in tree crowns, where they located cool shelters, spent nights, and presumably fed on honeydew. They formed high-density populations (310 adults/ha), exploiting high host plant abundance. They adhered to floodplains and to conditions of relatively mild winters. The ongoing Spiraea encroachment of abandoned alluvial grasslands is, thus, a transient situation, ultimately followed by forest encroachment. Rewilding the habitats by introducing native ungulates presents an opportunity to restore the disturbance regime of the sites. The increased resource supply combined with a warming climate has opened up temperate Europe to colonization by N. rivularis.

Ecological restoration and rewilding: two approaches with complementary goals?

As we enter the UN Decade on Ecosystem Restoration (2021-2030) and address the urgent need to protect and restore ecosystems and their ecological functions at large scales, rewilding has been brought into the limelight. Interest in this discipline is thus increasing, with a large number of conceptual scientific papers published in recent years. Increasing enthusiasm has led to discussions and debates in the scientific community about the differences between ecological restoration and rewilding. The main goal of this review is to compare and clarify the position of each field. Our results show that despite some differences (e.g. top-down versus bottom-up and functional versus taxonomic approaches) and notably with distinct goals - recovery of a defined historically determined target ecosystem versus recovery of natural processes with often no target endpoint - ecological restoration and rewilding have a common scope: the recovery of ecosystems following anthropogenic degradation. The goals of ecological restoration and rewilding have expanded with the progress of each field. However, it is unclear whether there is a paradigm shift with ecological restoration moving towards rewilding or vice versa. We underline the complementarity in time and in space of ecological restoration and rewilding. To conclude, we argue that reconciliation of these two fields of nature conservation to ensure complementarity could create a synergy to achieve their common scope.

Squamate scavenging services: Heath goannas (Varanus rosenbergi) support carcass removal and may suppress agriculturally damaging blowflies

Human-induced environmental change has caused widespread loss of species that support important functions for ecosystems and society. For example, vertebrate scavengers contribute to the functional health of ecosystems and provide services to agricultural landscapes by removing carcasses and associated pests. Widespread extirpation of native Australian mammals since the arrival of Europeans in Australia has removed many scavenging species from landscapes, while scavenging mammals such as European red foxes (Vulpes vulpes) have been introduced. In much of Australia, squamate reptiles are the largest native terrestrial scavengers remaining, where large native mammals are extinct and conservation management is being undertaken to remove invasive mammals. The contribution of reptiles to scavenging functions is not well understood. In this study, we investigated the ecosystem functions provided by large reptiles as scavengers to better understand how populations can be managed to support ecosystem services. We investigated the ecosystem services provided by vertebrate scavengers in Australian coastal mallee ecosystems, focusing on the heath goanna (Varanus rosenbergi), the only extant native terrestrial scavenger in the region. We carried out exclosure experiments, isolating the scavenging activity of different taxonomic groups to quantify the contribution of different taxa to scavenging services, specifically the removal of rat carcasses, and its impact on the occurrence of agriculturally damaging blowflies. We compared areas with different native and invasive scavenger communities to investigate the impact of invasive species removal and native species abundance on scavenging services. Our results indicated that vertebrate scavenging significantly contributes to carcass removal and limitation of necrophagous fly breeding in carcasses and that levels of removal are higher in areas associated with high densities of heath goannas and low densities of invasive mammals. Therefore, augmentation of heath goanna populations represents a promising management strategy to restore and maximize scavenging ecosystem services.

Trophic rewilding as a restoration approach under emerging novel biosphere conditions

Rewilding is a restoration approach that aims to promote self-regulating complex ecosystems by restoring non-human ecological processes while reducing human control and pressures. Rewilding is forward-looking in that it aims to enhance functionality for biodiversity, accepting and indeed promoting the dynamic nature of ecosystems, rather than fixating on static composition or structure. Rewilding is thus especially relevant in our epoch of increasingly novel biosphere conditions, driven by strong human-induced global change. Here, we explore this hypothesis in the context of trophic rewilding - the restoration of trophic complexity mediated by wild, large-bodied animals, known as 'megafauna'. This focus reflects the strong ecological impacts of large-bodied animals, their widespread loss during the last 50,000 years and their high diversity and ubiquity in the preceding 50 million years. Restoring abundant, diverse, wild-living megafauna is expected to promote vegetation heterogeneity, seed dispersal, nutrient cycling and biotic microhabitats. These are fundamental drivers of biodiversity and ecosystem function and are likely to gain importance for maintaining a biodiverse biosphere under increasingly novel ecological conditions. Non-native megafauna species may contribute to these effects as ecological surrogates of extinct species or by promoting ecological functionality within novel assemblages. Trophic rewilding has strong upscaling potential via population growth and expansion of wild fauna. It is likely to facilitate biotic adaptation to changing climatic conditions and resilience to ecosystem collapse, and to curb some negative impacts of globalization, notably the dominance of invasive alien plants. Finally, we discuss the complexities of realizing the biodiversity benefits that trophic rewilding offers under novel biosphere conditions in a heavily populated world.

A review of global wilderness area identification since the 21st century

Wilderness areas are natural landscape elements that are relatively undisrupted by human activity and play a critical role in maintaining ecological equilibrium, preserving naturalness, and ensuring ecosystem resilience. Since 2000, monitoring of global wilderness areas has increased owing to the availability of spatial map data and remote sensing imagery related to human activity and/or human footprint. Progress has been made in the remote sensing of wilderness areas by relying on available historical literature (e.g., published papers, books, and reports). However, to our knowledge, a synthesis of wilderness area research from a remote sensing perspective has not yet been performed. In this preliminary review, we discuss the concept of wilderness in different historical eras and systematically summarize dynamic wilderness monitoring at local, national, and global scales, available remotely sensed indicators, disparities and commonalities in identification methods, and mapping uncertainties. Finally, since this field remains in its initial stage owing to a lack of unified standards and vertical/horizontal comparisons, we present insights into future research directions, particularly with regard to remote sensing. The findings of this review may help to improve the overall understanding of current wilderness patterns (i.e., increases/decreases) and the mechanisms by which they change, as well as provide guidance for global nature conservation programs.

Into the wild: uncertain frontiers and sustainable human-nature interactions

Humans seldom consider themselves as animals, and that humans are animals is a truth frequently turned into an insulting metaphor indicating "uncivilized" behavior in many cultures. Interestingly, the "civilizing" aspects of Western Culture in the Global North are historically derived from traditions of democracy based on living in cities from which the wild has been banished. This is embedded in the English language since civilizing and civilization come from the Latin for city, civitas, the place where citizens hold voting rights. Beyond the gates of civilization is the wild. How the wild and nature have been constructed and demarcated is an enormously complex and enduring challenge in western philosophy as it relates to knowledge-making, existence, truth, and reality. Indeed, whilst people generally believe they know what nature means, they rarely realize that little in nature is wild. Furthermore, the concept of uncertainty, central to the pandemic, is compounded by climate instability and a potentially disastrous future. This is breaking down what is known, requiring porous and flexible conceptual frontiers and a transdisciplinary approach. This article traces the linguistic separation of humans from their animal origins and wilder environments for political and increasingly greedy economic purposes. It explores the acknowledged complexity of healthy human-nature interactions, juxtaposing information mainly from the humanities and social sciences. Demonstrating how unhealthy the current paradigm has proven to be for humans and the natural world, it brings together conflicting information to disrupt traditional certainties using an innovative bricolage methodology. It weaves and combines different ways of knowing as it considers forms of knowledge-making, rewilding, foraging, the place of magical thinking, and vital force. It concludes that a new paradigm is needed to enable a way of working toward any vision of healthy human-nature interaction.

Long-term vegetation trajectories to inform nature recovery strategies: The Greater Côa Valley as a case study

Active and passive approaches to rewilding and ecological restoration are increasingly considered to promote nature recovery at scale. However, historical data on vegetation trajectories have rarely been used to inform decisions on whether active or passive management is most appropriate to aid recovery of a specific ecosystem, which can lead to sub-optimal approaches being deployed and reduced biodiversity benefits. To demonstrate how understanding past changes can inform future management strategies, this study used satellite remote sensing data to analyse the changes in land cover and primary productivity within the Greater Côa Valley in Portugal, which has experienced wide-scale land abandonment. Results show that some areas in the Valley regenerated well following land abandonment in the region, leading to a more heterogeneous landscape of habitats for wildlife, whereas in other areas passive recovery was slow. As Rewilding Portugal intensifies its nature recovery efforts in the region, this study calls for strategic deployment of passive and active approaches to maximise conservation benefits. More broadly, our results highlight how baseline vegetational trajectories and contextual information can help inform whether active or passive management approaches may be suitable on a site-by-site basis for both rewilding and restoration projects.

Naturalness and principle pluralism in conservation

The concept of naturalness in biodiversity conservation remains polysemic, hampering decision-making. Although some conservationists claim ecosystem naturalness should be primarily determined by composition (integrity), others argue it should be determined by the extent of freedom from anthropogenic influence (autonomy). Problems arise when deciding how to treat affected ecosystems. Although the integrity school promotes benchmark-based active restoration, the autonomy school advocates a hands-off policy, making these 2 approaches contradictory. Moreover, expected global changes have promoted advocacy for ecosystem resilience, further complicating the debate. We argue that autonomy, integrity, and resilience are all morally valid. The conflict between them is contained by recognizing that full naturalness is an unattainable goal; restoration and rewilding processes are not an act of curation, but a contrary-to-duty obligation; principle pluralism can accommodate integrity, resilience, and autonomy as pro tanto principles in a case-specific approach; and naturalness, as an overarching value, gives unity to the plurality of principles.

Public attitudes and intentions toward engaging in reintroduction of wolves to Japan

Reintroducing apex predators is an important approach in ecosystem restoration; however, it is challenging. Wolves (Canis lupus) were exterminated in Japan around 1900, and since then, there has been a lack of top predators throughout the country. Currently, the wild ungulate population is increasing, causing agricultural and forest damage. This has triggered an ongoing debate among researchers and nongovernmental organizations on whether wolves should be reintroduced to promote self-regulating biodiverse ecosystems. We conducted a nationwide survey to examine public attitudes toward wolf reintroduction (WR) in Japan. We sent online questionnaires to 88,318 citizens across the country. Among the 12,028 respondents, excluding those with invalid or incomplete answers and unqualified respondents, we obtained and analyzed 7500 responses that were representative of Japanese citizens in terms of some key sociodemographic attributes. More respondents disagreed with WR (39.9%) than agreed (17.1%), and many respondents (43.0%) were undecided. Structural equation modeling revealed that risk perceptions affected public attitudes, implying that the greater the perceived threat of wolf attacks, the less likely people are to support WR. In contrast, attitudes toward wolves (e.g., "I like wolves.") influenced by wildlife value orientation and beliefs about the ecological role of wolves (e.g., controlling deer populations) positively affected public attitudes toward WR. Those who had a positive attitude toward WR showed intentions to engage in behaviors that support WR. Our results suggest that the dissemination of information related to the ecological role of wolves and the development of a more mutualistic mindset in people could positively influence public support for WR in Japan.

Large mammals and trees in eastern monsoonal China: anthropogenic losses since the Late Pleistocene and restoration prospects in the Anthropocene

Massive human-induced declines of large-sized animals and trees (megabiota) from the Late Pleistocene to the Anthropocene have resulted in downsized ecosystems across the globe, in which components and functions have been greatly simplified. In response, active restoration projects of extant large-sized species or functional substitutes are needed at large scales to promote ecological processes that are important for ecosystem self-regulation and biodiversity maintenance. Despite the desired global scope of such projects, they have received little attention in East Asia. Here, we synthesise the biogeographical and ecological knowledge of megabiota in ancient and modern China, with relevant data mostly located in eastern monsoonal China (EMC), aiming to assess its potential for restoring functionally intact ecosystems modulated by megabiota. We found that during the Late Pleistocene, 12 mammalian megafaunal (carnivores ≥15 kg and herbivores ≥500 kg) species disappeared from EMC: one carnivore Crocuta ultima (East Asian spotted hyena) and 11 herbivores including six megaherbivores (≥1000 kg). The relative importance of climate change and humans in driving these losses remains debated, despite accumulating evidence in favour of the latter. Later massive depletion of megafauna and large-sized (45-500 kg) herbivores has been closely associated with agricultural expansion and societal development, especially during the late Holocene. While forests rich in large timber trees (33 taxa in written records) were common in the region 2000-3000 years ago, millennial-long logging has resulted in considerable range contractions and at least 39 threatened species. The wide distribution of C. ultima, which likely favoured open or semi-open habitats (like extant spotted hyenas), suggests the existence of mosaic open and closed vegetation in the Late Pleistocene across EMC, in line with a few pollen-based vegetation reconstructions and potentially, or at least partially, reflecting herbivory by herbivorous megafauna. The widespread loss of megaherbivores may have strongly compromised seed dispersal for both megafruit (fleshy fruits with widths ≥40 mm) and non-megafruit plant species in EMC, especially in terms of extra-long-distance (>10 km) dispersal, which is critical for plant species that rely on effective biotic agents to track rapid climate change. The former occurrence of large mammals and trees have translated into rich material and non-material heritages passed down across generations. Several reintroduction projects have been implemented or are under consideration, with the case of Elaphurus davidianus a notable success in recovering wild populations in the middle reaches of the Yangtze River, although trophic interactions with native carnivorous megafauna have not yet been restored. Lessons of dealing with human-wildlife conflicts are key to public support for maintaining landscapes shared with megafauna and large herbivores in the human-dominated Anthropocene. Meanwhile, potential human-wildlife conflicts, e.g. public health risks, need to be scientifically informed and effectively reduced. The Chinese government's strong commitment to improved policies of ecological protection and restoration (e.g. ecological redlines and national parks) provides a solid foundation for a scaling-up contribution to the global scope needed for solving the crisis of biotic downsizing and ecosystem degradation.

Ecosystem restoration, regeneration and rewilding

Anthropomorphic activities have caused major damage to ecosystems worldwide. Although documenting this damage is important, implementing measures to halt and reverse ecosystem decline is critical and is now being prioritised globally. To support global goals to protect and restore nature, BMC Ecology and Evolution has launched a new article collection to encourage contributions from the multifaceted ecosystem restoration community.

Prehistoric pathways to Anthropocene adaptation: Evidence from the Red River Delta, Vietnam

Over the past twenty years, government advisory bodies have placed increasing emphasis on the need for adaptive measures in response to the effects of human-induced climate change. Integrated Assessment Models (IAMs), which incorporate macroeconomic and climate variables, feature prominently in advisory content, though they rarely draw on data from outside strictly constrained hypothetical systems. This has led to assertions that they are not well-suited to approximate complex systemic human-environment processes. Modular, interdisciplinary approaches have offered a way to address this shortcoming; however, beyond climate records, prehistoric data continue to be under-utilised in developing such models. In this paper we highlight the contribution that archaeology and palaeoecology can make to the development of the next generation IAMs that are expected to enhance provision for more local and pro-active adaptations to future climate change. We present data from one of Southeast Asia's most heavily developed river deltas: the Red River (Song Hong) Delta, in Vietnam and localised analysis from the Tràng An Landscape Complex World Heritage Site, on the delta's southern margin. Comparison is made between Shared Socio-economic Pathways (SSP) 5-8.5 and SSP2-4.5 emission projection models and the Mid-Holocene inundation of the Red River Basin. We highlight the value to taking a scientific long view of coastal evolution through an illustrative set of eight research foci where palaeo-data can bring new and localised empirical data to bear on future risk management planning. We proceed to demonstrate the applicability of palaeoenvironmental, zooarchaeological and historical evidence to management and the development of sustainable conservation strategies using Tràng An as a case study. In so doing, we further highlight the importance of knowledge exchange between scientific, corporate, non-governmental, local, and state stakeholders to achieve tangible results on the ground.

Contrasting seasonal patterns in diet and dung-associated invertebrates of feral cattle and horses in a rewilding area

Trophic rewilding is increasingly applied in restoration efforts, with the aim of reintroducing the ecological functions provided by large-bodied mammals and thereby promote self-regulating, biodiverse ecosystems. However, empirical evidence for the effects of megafauna introductions on the abundance and richness of other organisms such as plants and invertebrates, and the mechanisms involved still need strengthening. In this study, we use environmental DNA (eDNA) metabarcoding of dung from co-existing feral cattle and horses to assess the seasonal variation in plant diet and dung-associated arthropods and nematodes. We found consistently high diet richness of horses, with low seasonal variability, while the generally lower dietary diversity of cattle increased substantially during summer. Intriguingly, season-specific diets differed, with a greater proportion of trees in the horses' diet during winter, where cattle relied more on shrubs. Graminoids were predominantly found in the diet of horses, but were generally underrepresented compared to previous studies, possibly due to the high prevalence of forbs in the study area. Dung-associated arthropod richness was higher for cattle, largely due to a high richness of flies during summer. Several species of dung-associated arthropods were found primarily in dung from one of the two herbivores, and our data confirmed known patterns of seasonal activity. Nematode richness was constantly higher for horses, and nematode communities were markedly different between the two species. Our results demonstrate complementary effects of cattle and horses through diet differences and dung-associated invertebrate communities, enhancing our understanding of large herbivore effects on vegetation and associated biodiversity. These results are directly applicable for decision-making in rewilding projects, suggesting biodiversity-benefits by inclusion of functionally different herbivores.

A bolder conservation future for Indonesia by prioritising biodiversity, carbon and unique ecosystems in Sulawesi

As more ambitious protected area (PA) targets for the post-2020 global biodiversity framework are set beyond Aichi Target 11, renew thinking into spatial prioritisation is required to enable PA expansion that maximises environmental values. Our study focuses on the biodiverse and forest-rich Indonesian island of Sulawesi, which has a terrestrial PA network that covers 10% of the island. We used Marxan to investigate trade-offs in the design of an expanded PA network that prioritised different conservation features (biodiversity, forest cover, carbon stock, karst and valuable metal-rich areas) under varying island-wide coverage targets (17%, 30%, and 50%). Our first scenario, which required existing PAs to be selected, required larger areas to meet these coverage targets, in contrast to our second scenario, which allowed for any part of the island to be chosen, irrespective of PA status. The vast Mekongga and Bangkiriang Landscapes, and Gorontalo corridor were consistently identified as a high priority for protection under all scenarios. To meet our conservation targets through expanding current PAs, creating new PAs, and creating corridors that connect existing PAs, we used a spatially explicit three-phase approach. Our findings identified 26,508 km² of priority areas to be included in the current PA network, potentially assisting Indonesia in meeting its post-2020 GBF target, if our approach is replicated across Indonesia as a national or sub-national analysis. We discuss various land management options through other effective area-based conservation measures (OECMs) and the costs to deliver this strategy.

Active versus passive restoration: Forests in the southern Carpathian Mountains as a case study

Active and passive restoration are both increasingly considered as options for nature recovery, with potential to help address the current climate and biodiversity crises. So far, however, there is little practical information on how to gauge the benefits and limitations of each approach, in terms of their effects on large-scale ecosystem composition, structure, and functioning. To address this knowledge gap, this study used satellite remote sensing to investigate changes in land cover and primary productivity within the forests of the Făgăraș Mountains in southern Romania, where large-scale restoration and land abandonment have simultaneously taken place across the past two decades. To our knowledge, this study is the first to contrast the impacts of active and passive restoration within a single landscape on components of ecosystem structure and functioning at such temporal and spatial scales. Results show active restoration activities to be very effective at facilitating the recovery of cleared forests in small parts of the landscapes; but they also highlight substantial areas of natural forest expansion following agricultural abandonment, in line with regional trends. Altogether, our approach clearly illustrates how freely available satellite data can (1) provide vital spatially explicit insights about large-scale and long-term transformations in ecosystem composition, structure and functioning; and (2) help contrast the impacts of restoration approaches on vegetation distribution and dynamics, in ways that complement existing ground-based studies.

Vegetation Changes Following Large-scale Fence Removal Across a Protected Area Network Within the Kruger to Canyons Biosphere Reserve, South Africa

In the early 1990’s, reserves adjacent to Kruger National Park (KNP) removed their fences to create a continuous landscape within the Kruger to Canyons Biosphere Reserve. Understanding how these interconnected multi-management systems responded to changes in environmental factors and management regimes can help to maintain natural large-scale landscape heterogeneity and ecological resilience. Our objective was to analyze remote sensing-derived vegetation metric changes between the different management types pre- and post-fence removal. The study area included fourteen reserves and the central section of KNP. We calculated the residuals between TIMESAT-derived metrics (from AVHRR NDVI time series) and rainfall to analyze changes in vegetation from 1985 to 2006. We then compared vegetation-rainfall residuals between different management types pre- and post-fence removal using mean–variance plots, nonmetric multidimensional scaling plots, and permutational multivariate analysis of variance to statistically identify and analyze changes. All management types experienced increased greenness. Reserves that removed their fences had greater changes in vegetation post-fence removal compared to reserves that remained fenced and KNP. Our findings suggest managers may need to address landscape changes by implementing management regimes such as reducing artificial surface water to counterbalance increased grazing pressure as a result of increased animal mobility across artificially created resource gradients. Habitat connectivity within and between protected area networks can be achieved by removing fences across adjacent conservation areas thus potentially increasing ecological resilience, which is vital to effective long-term conservation.

Humans, megafauna and landscape structure – Rock engravings from Namibia encourage a comparative approach to central Europe and southern Africa

This paper deals with reflections that arose after observing prehistoric rock engravings at different locations in Namibia. These observations stimulated comparative considerations with focus on southern Africa and central Europe. Similar to the Aurignacian rock art of European origin, the most common motifs in the Namibian rock engravings are large animals. While in Europe, the species that served as a blueprint for the illustration of Aurignacian rock art have mostly disappeared, the megafauna illustrated on the rock engravings in Namibia can still be found in the immediate vicinity of the rock art. Against this background, we discuss and further develop a comparative regional approach. We reconstruct and evaluate the suitability of African savannas and still-existing megafauna communities as an appropriate reference-frame for natural European grassland systems and extinct associated warm-adapted megafauna (Eemian Interglacial megafauna). Special attention is laid on the unique situation in Africa in the light of a global extinction wave of megafauna following increasing human activity in the Late Quaternary. This leads us to discuss the use of domesticated ungulates as surrogate taxa to fulfill ecosystem functions in Europe as part of concepts termed “rewilding” or “naturalistic grazing”. After critically examining these concepts, we conclude that using domesticated forms as representatives of extinct or locally disappeared species in Europe has its justification to some extent. If, however, the naturally occurring megaherbivore community still exists (Africa), these naturally occurring species should be given priority due to their organismic abilities and limitations adapted to the harsh conditions in their specific environment. Finally, we discuss the application of (transboundary) protected areas as effective instruments to mitigate human-wildlife conflicts. A holistic approach, including nature conservation and preservation of cultural achievements (domesticated forms, grazing systems), appears promising for the effective protection of the natural African savanna ecosystems with their unique fauna elements, as illustrated in rock engravings that inspired us to write this paper.